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Birding Business

This month’s bird

The Hairy Woodpecker

Birding Business: Dec. 2011

Searching for Knowledge

BY RAY DAVID | Publisher

If you think about it, at any given moment we're at the pinnacle of our knowledge about feeding wild birds

RESEARCH, BEING AT ALL TIMES A WORK IN PROGRESS, brings new information to light sporadically over the course of time which updates what we know, and impacts how we feed birds and develop new blends and products to improve the experience. The question that comes to my mind is, what new discoveries are currently being evaluated?

One of our valued sources of such information is Mario Olmos, an ornithologist and researcher involved in bird food nutrition studies for Kaytee Products Inc. in Chilton, Wisconsin. Starting with what we already know about the feeding habits of backyard seed-eating birds, Mario and his team wanted to determine why certain species preferred a particular seed, what benefits do those seeds provide to the individual species, and how can this information be used to attract more birds to feeders. This is his report:

Preferences and Benefits:High fat content in seeds seems to be the most important component for wild birds. It is very helpful in their daily routine, which requires a lot of energy no matter which time of the year. Breeding, feeding the young, migration, all require fat foods for energy. Throughout the year birds go through several biological changes that require specialized nutrition, not just fat. Seed mixes provide some of the extra nutrients, but not all of them. Also, some seeds have natural pigments that help birds achieve their striking colors, such as red and yellow, but not in the amounts required by some species. The nutritional needs during molting, breeding, immature stages, migration and wintering are not all provided in seed mixes. The calcium requirement during breeding season is a good example of how birds will search and hunt for this mineral not found in most seeds. Some seed mixes have calcium added based on data from studies of poultry and pet birds. But wild birds are different. We must be careful with the application of calcium, especially when combined with other vitamins. Some of the possible results can lead to embryo deficiencies. Supplemental vitamins or minerals in wild bird food should be supported by studies of wild birds' nutritional needs.

The non-stop expansion of urbanism is bringing bird species closer to humans. Many species are quite common in our backyards, and go through their entire life cycles among us. Urban gardens have become important nesting sites for many birds, such as Northern Cardinal, House Finch, and Chickadees. Comparison studies of breeding and clutch success indicate that birds in the wild are more successful breeders than urban birds. These studies point to the food factor as one of the main problems for birds in urban areas. The lack of insects due to pesticides and insect control, endemic fruits, berries, native grasslands and invasive species all become a disadvantage for urban birds when compared with birds in the forest or in rural areas. The seeds in our feeders can provide a basic supplemental food source that can help wild birds throughout the year. In areas where species are low in numbers, supplemental feeding is definitely a great support for the recovery of those species.

Color and Color Vision:Birds get all their information about their environment through their eyes. Color perception is very important for courting, finding food and migration. Birds have more complex visual systems than we do. We are trichromats, having photo-pigments with sensitivities at 3 peak wavelengths, while birds have photo-pigments at 4 or 5 peak wavelengths, making them true tetrachromats, or perhaps even pentachromats. In some species the visual spectrum extends into the ultraviolet range, where it will be impossible for humans to perceive colors.

The study of birds' perception of color is a very difficult task. This impacts the study of bird behavior, how birds use color contrast to navigate during migration, classify objects in their environment such as a feeder and bird food, and interact socially and sexually.Considering that birds require the use of their color vision to find food, our R & D department, in collaboration with Arizona State University, Auburn University and Purdue University, has conducted several feeding and behavioral studies in color perception. These studies show that birds use their color vision to find their food, and also that color contrast is highly important to identify objects. Our scientists were able to prove color preferences in seeds among different species, regardless of shape, and how color contrast in a seed mix can be very important in seed selection. These new studies and technology will help in the development of better seed mixes that could bring a better feeding experience to consumers. Also, the studies of color perception will help with feeder color and placement.Hummingbird Electronectar:This study examined electrolyte and water balance in the Ruby-throated Hummingbird (Archilochus colubris), the most common visitor to backyard hummingbird feeders in the Mid-West and East.

Nectarivorous hummingbirds consume up to 5 times their body mass in nectar each day, but ironically this exposes them to probable dehydration when consuming solutions that do not contain electrolytes. Hummingbirds quickly process excess water while drinking, which serves to return body mass to pre-feeding status and reduces the ill-effects of excess circulating water. The hummingbird kidney experiences obligatory loss of electrolytes, so when hummers do not consume electrolytes in their diet they will experience a net loss of electrolytes. When the amount of electrolytes in the body drops the concentration of water will also drop as the body acts to maintain a constant electrolyte concentration. This can lead to dehydration and weight loss.

Mario and his team are currently working on more detailed analyses of bird food and nutrition which will be available for publication at a later date. We'll update you on those results as they come in. In the meantime research continues at various other bird food packers, and we'll pass along the detail as it comes to us.

IN THIS ISSUEDon't Overlook the Book! Educating kids is part of our responsibility.Don't Overlook the Bookby Michael Anderson